Sewing machine



vvMay 7, 1935.

F. RICKS ET AL SEWING MACHINE Filed Oct. 25, 1953 4 Sheets-Sheet lllllll mm 0 M May 7, 1935. F. RICKS EI' AL SEWING MACHINE 4 Sheets-Sheet2 Filed Oct. 25, 1933 y 1935. F. RICKS El AL 2,000,613

SEWING MACHINE Filed Oct. 25, 1935 4 sheets-Sheet 3 y 1935- F. RICKS ETAL ,000,613

SEWING MACHINE Filed Oct. 25, 1955 51 41 4 thread. I The above and otherobjects, and the Patented May 7, 1935 2,000,613 SEWING MACHINE I FredRicks, Harold Ernest Elliott, and Frank Coleman Choice, Leicester,England, assignors to United Shoe Machinery'Corporation, Paterson, N.J., a corporation of New Jersey Application October 25, 1933, Serial No.695,140 a In Great Britain November 4, 1932 16 Claims.

The present invention relates to sewing machines, and particularly, butby no means exclusively, to hooked needle sewing machines such as areused, for instance, in the manufacture of shoes.

The invention will be explained by way of illustration and not oflimitation in connection with curved hooked needle chain stitch sewingmachines of which the machine illustrated and described in the patentsto Eppler No; 1,108,560 dated August 25, 1914 and Topham No. 1,099,328dated June 9, 1914 is an example.

In machines of the type disclosed in the patents above referred to thetension exerted on the thread by the agency of the usual tension deviceplays an important part in determining the proper formation of the seamand requires to be adjusted with some nicety to deal with changing workconditions. The usual tension device is a friction device and the actualtension being exerted in any given circumstances -of adjustment is not,therefore, reliably constant or readily ascertainable by the operator ofthe machine and the disturbance, tomeet other conditions, of a conditionof adjustmentfound by trial and error appropriate to one class ofworkmakes it a matter of no small difiiculty for the operator to restorethe same tension conditions when he so desires.

It is, one of the several objects of the present invention to providemuch increased facilities for effecting such restoration of conditionspreviously determined as appropriate to a given case while it is anotherof the severalobjects of the invention to provide tension devices forsuch machines which shall reliably create, asdesired, tension of adeterminate amount.

With the above objects in view one of the several features ofthe-invention contemplates the provision in a sewing machine of'a threadtension device having a novel and improved construction and mode ofoperation, which device acts to create tension by the storage of energyin the device under the pull of the thread.

' Other features of the present invention contemplate the provision of anovel and improved means for'adjusting a thread tension device, and anovel and improved means for indicating to the operator of the machinethe condition of the adjustment or, in other words, the amount oftension exerted by the tension device on the several features of theinvention'will become evident to those skilled in the art .from thefollowing description of illustrative constructions according to theinvention given by way of example.

Referring to the drawings, Figure 1 is a view in side elevation, partlyin section, of a curved hooked needle chain stitch'shoe sewing 7:;

machine of the type illustrated in the patents above referred toembodying a form of the present invention; Figure 2: is a verticalsectional view of the thread tension mechanism illustrated in Figure 1,taken substantially on a plane indicated by the line 22; Figure 3 is aview similar to Figure 2 illustrating a slightly different form ofthread tension mechanism Figure 4 is a detail sectional view taken on aplane indicated by the lines 44 in Figures 2 and 3; Figure 5 is a detailsectional view taken on a plane indicated by the line 5-5 on Figure 2;and Figure 6 is a detail sectional view taken on a plane indicated bythe line 6-6 in Figure 3.

The machine illustrated in Figure 1, except as hereinafter described, isthe same in the construction and mode of operation of its various partsas the machine disclosed in the patents above referred to. The curvedhooked needle "of the machine is indicated at 3|, the looper at 3 2, thethread finger at 33, the take-up at 34 and the auxiliary take-up at 35.During the operationof these devices in forming a stitch the take-upacts to draw the last needle loop tight around the shank of the needlewhile the needle is through the work and then to draw thread from thesupply, the tension wheel, indicated at 36, being rotated by the pull ofthe thread during this action of the take-up. During the loop drawingstroke of the needle 3|,

thread is given up to the needle by the take-up groove 'torreceive thethread. The discs are secured to the right hand end of a horizontalspindle 38 extending fromright to left of the machine, which spindle isrotatably mounted in a bracket 39 secured to the rear of the machineframe.

The tension wheel spindle has secured to it close to the tension wheelan internally coned clutch member 40 which is engaged at a certainmembers are in engagement, the tension wheel is prevented from rotating.The externally coned clutch member is urged by a spring 43 surroundingthe spindle into engagement with the internally coned member and iswithdrawn by links 44 which are connected to the pins 42 extending fromthe member, said pins entering slots in the links. The links extend'fromthe pins to the left substantially parallelto the tension wheel spindleand at their other ends are pivotally connected to a forked downwardlyextending arm 45 of a three-armed lever 46 pivotedon a horizontal shaftv41 extending forwardlyand rearwardly of the machine and fixed in thesaid bracket above the tension wheel spindle. Anotherarm 48 of thethreearmed lever extends to the rightfrom the hub of the lever an'disconnected by a link 49 to a cam lever 50 of the machine which controlsthe thread tension, as hereinafter described. A second externally conedclutch member 5| is keyed to the tension wheel spindleso as, to slidethereon and rotate therewith and is arranged to the left of the firstclutch members. The second externally coned clutch member is urged bythe spring 43 into engagement with a second internally coned clutchmember 52. The

secondexternally coned clutch member is withdrawn by the same forked arm45 of the threearmed lever aforesaid which controls the first externallyconed clutch member, which forked arm carries blocks engaging a flangeon the second clutch member, and the arrangement is such that when oneexternally coned clutch member is allowed to be moved by the spring 43into clutching engagement with its internally coned member theiother,clutch member is withdrawn. .Th second internally coned clutchmember is formed on the right-hand side of a drum .53 which is freelyrotatable on the tension. wheel spindle; Arranged inside the drum aboutthe axis of the spindle is a clock spring 54 one end of which is securedto the drum and the other .end of which is securedto a member 55 withinthe drum. The latter member is formed on the right-hand end of a shaft56 mounted in bearings in the aforesaid bracket 39 in axial alignmentwith the tension wheel spindle. The latter shafthas at its left. handend a hand-wheel 5'! bywhich it may be. ro-

tated to wind up the clock spring and a ratchet wheel 58 on the shaftand a hand releasable pawl 59 prevent the shaft from returning except asand when desired. The drum is prevented from rotating under theinfluence of the spring when the spring is wound up by the engagement ofa lug 60 on the drum with a lug 6| on the bracket. The shaft 56 haspn ita spiral gear 62 which meshes with a spiral gear segment on an indicatorarm. pivoted on the bracket and the indicator arm isarranged to swingover a scale 63 on the bracket when the shaft is rotated to adjust thespringto indicate to the operator on the scale which is situated to bereadily visible from the front of the machine the actual tension ofthespring.

4 When, during the operation of the machine under the pull of thethread.

the take-up lever is setting the previously formed stitch and is pullingthread from the supply the second externally coned clutch member 5| isin engagement with the second internally coned clutch member 52 and thefirst clutch is disengaged. The tension wheel is therefore connectedthrough the second clutch and drum to one end of the clock spring which,as the takeup is moving in a direction to set the previous stitch anddraw thread from the supply is further wound up (it being understoodthat the thread lapped round the wheel cannot slip around the same) andthrough the tension Wheel exerts tension on the thread, the final amountof tension being primarily dependent upon the previous adjustment of thehandwheel and to a lesser degree on the extent of rotation-of thetension wheel. After the takeup has finished its movement to set theprevious stitch and draw thread from the supply, the second clutch isopened and the first clutch is closed (so that in effect the tensionwheel is locked) and the drum is returned by the clock spring until thelug 60 on the drum engages the lug 6| on the bracket. At the time in themachine cycle when the needle is moving back and pulling aloop of threadthrough the work and exerting a pull on the preceding loop, the

first clutch is closed and the second clutch is open and the tensionwheel is prevented from rotation. .To allow the needle to obtain threadduring its backward movement without drawing thread from the supply, thestop plunger 31 against which the auxiliary take-up is moved by the pullof the needle on the thread before the needle reaches its fully backposition is in the construction being described arranged to 'yield atthis time against a light spring indicated at 620. so that. the needlemay obtain .by such yield thread during its final backward movement bymovement of the auxiliary takeup. To insure a certain and uniformyielding strain on the thread as the needle reaches the limit of itsloop drawing stroke without pulling thread from thesupply, means areprovided in theillustrated construction for locking the a1lX- iliarytake-up against yielding movement during the action of the take-up indrawing thread from the supply. As illustrated in Figure l,

the auxiliary take-up is held against the yielding movement during thethread drawing action of the take-up by means of a locking slide 833arranged in av horizontal guideway above a pin '64 projecting from thestop plunger 31. The slide 530 is pivotally connected at its rear .endto an arm 640 projecting upwardly from the hub of the take-up lever 84.The lower surface of the slide 630 is provided with a notch which,during the backward loop drawing stroke of the needle, allows the stopplunger 31 to yield to the desired extent. During the loop drawingstroke ofthe take-up, however, the notch in the slide 630 is moved outof the path of thepin 64, and the stop plunger is locked so as toprevent the auxiliary take-up from rising In this way drawing of thethread from the supply is effected solely by the main take-up and theneedle does. not have to pull any thread from the supply and is notsubject to the heavy pull of the clock spring.

As in the case of the machines disclosed in the patents above referredto, the illustrated 7 machine maybe stopped, either manually orautomatically when sewing is discontinued, with .55 pivoted on thebracket 39. One arm of the bell cr'anklever 65 engages one of thepins 42extending from the clutch member 4|and1the other arm of the bell cranklever. carries a latch 68 pivotally mounted at its lower end-on thehorizontal arm of the bell crank andextending upwardly into a positionto be engaged by a projection on the hub of a lever 67' (see Fig. 1)mounted on the frame of the bracket 39. A leaf spring 68 attached to thelever 61 bears upon the latch 56 and holds it in the path of theprojection from the hub of the lever. The upper end of the lever 61 isconnected by a link 69 to the lower end of an arm 10 projectingdownwardly from a rock shaft 1| extending across the machine at the rearof and below the main cam shaft 12. As fully described in the patentsabove referred to, the shaft II is rocked in a clockwise direction asviewed in Figure 1 upon stopping the machine. This movement of the rockshaft through the connections above described swings the bell cranklever 65 in a direction to open the clutch 4|. This movement .of theclutch 4| is permitted by the slotted connection between the links 44and the pins 42.

To insure the necessary quick return of the drum 53 by the clock spring54 it may be desirable to additionally drive the drum .inzits returnmovement and this may be effected by a continually rotating pulley I3rotatably and slidably mounted on the shaft 56 which pulley, when theclutch 5| is open, is automatically clutched momentarily to the drum 53by clutch members I4 and I5 formed respectively on the drum 53 and thepulley. The clutch l4, I5 is convenientlycontrolled by connections tothe third arm 16 of the three-armed lever 45. As illustrated in Figure3, the hub of the pulley '|3 bears against a thrust bearing 11 which isengaged by the lower forked end of a lever 18, the upper end of which isyieldingly connected to the upper end of the arm 18 of the three-armedlever 46 by means of a link 19 and spring 80, the link 19 beingpivotally connected-at one end to the arm 16 and at its other endpassing loosely through the upper end of the lever 18, and the spring 80being interposed between the lever 18 and a collar 8| fast on the link;With this construction, the pulley I3 is yieldingly forced towards thedrum 53 when the clutch member 5| is moved away from the clutch member52. The drum 53 is thus returned against its stop with certainty afterwhich the clutch members l4, 15 are allowed to slip until they arepermitted to separate upon the movement of the clutch member 5| towardsthe member 52.

During each stitch forming cycle of the machine the'tension wheel 36 isrotated about 130 as the take-up draws thread from the supply, and suchmovement may-be found to unduly tension the clock spring 54 which willbe wound up by the rotation of the'tension wheel. To prevent such unduetensioning ofthespring 54, the tension mechanism illustrated in Fig. 2may be used, which mechanism, except as hereinafter described is thesame in the construction and .which the spring has been adjusted, aspiral arrangement of its various partsas themechanism. illustrated inFig. 3', and above described.

In the construction illustrated in Fig. 2, the

tension adjusting member 55 to which one. end of the. clock spring '54is connected, instead of being held in fixed position in the bracket 39is driven by connections to the main take-up cam lever in such a mannerthat as the rotationof the tension wheel, when the take-up is settingthe previous stitch and drawing thread from the supply, tends to Wind upthe clock spring 54 .by, in effect, a pull on one end of the spring, the

other end of the spring is moved round in the" same direction, but at aslightly higher speed 'so that the initialtension of the clock spring ismaintained substantially constant during the) rotation of the tensionwheel. As illustrated in Figs. 1 and 2, the connections between the maintake-up cam lever and the tension adjusting member 55 comprise a pinion82. mounted'to rotate with and slide longitudinally on the shaft I 56, agcar segment 83 meshing with the pinion 82, a rock shaft 84 to which thegear segment 83=is secured, an arm 85 secured to the rock shaft 84, anda link 85 connecting the arm .85 with the main take-up lever. h 1

In order torpermit :the adjustment of the spring 54 in the constructionillustrated in Fig. 2, means are provided whereby the tension adjustingmember 55 may be disconnected from the main take-up lever and rotatedindependently to a new position of adjustment. To this end, in theconstruction illustrated in Fig. 2 the pinion 82 is mountedto be capableof sliding longitudinally on the shaft '56 so as to disengage the pinionfrom thegear segment 83 and bring it into mesh with an internal gear 81formed on the inner end of a sleeve 88moun ted on the shaft 56. Thepinion 82 may be moved back and forth on the sleeve 55 by a manuallyoperable rod 89, the inner end of which is provided. with a yoke 98engaging a slot. in the pinion 82 and the outer end of whichis'.provided with a locking projection 9| arranged to engage any one ofa series of locking notches formed in arsleeve 92 fast on the sleeve 88.;A spring 93 coiled around the rod 89 and interposed between the yoke 90and a shoulder on the fixed bracket 39 tends to force the rod 89 to theleft, as viewed in Fig. 2 and holds the pinion 82 in mesh with the gearsegment 83. With the parts in their normal position, as illustrated inFig. 2, the locking projection 9| is in engagement with the notches onthe sleeve 92 and thus this sleeve, together with the sleeve 88 is heldfrom rotation. With the parts'in this posigear 81 and, at the same time,the locking projection 9| moves out of engagementwith the notches on thelockingsleeve 92. The sleeve88 ,isnow free to be rotated by the handwheel 94 at its outer end, and this rotation through the internal gear-8'! and pinion 82 rotates the tensionadjustingmember 55 to secure thedesired adjustment of the spring 54. After the desired adjustment hasbeen secured the pinion 82 is returned into engagement with the gearseg-- ment 83 and the locking projection 9| again engages the notches.of'the sleeve 92.

To indicate to the operator the tension to gear 95 is formed on thesleeve 92 which meshes with a spiral gear segment on an indicator armpivoted on the bracket 39 and arranged to swing over the scale 63 on thebracketwhen the sleeve 88 is rotated to adjust the spring. As abovestated, this scale is situated so as to be readily visible to theoperator from the front of the machine. a v I In the constructionillustrated in Fig. 2, the rotating pulley E3 of the constructionillustrated in Fig. 3 -is dispensed with and the drum 53 is returned by'means of a finger 96 on the tension adjusting member 55 arranged toengage a lug 91 on the drum. To permit the finger 98 and lug 91 tocooperate properly under alladjustments of the spring 54, the lug 91 isadjustably mounted ina circumferential slot 98 in the periphery of thedrum and is held in adjusted position we looking nut 99 having a screwthreaded engagement with astud projecting outwardly from the lug 91through the slot 98. x 1 'As has beenstated, the connections from themain'take-up lever to'the tension adjusting member 55 are arranged tomove the member 55 at a slightly higher speed than that of the drum"'53.The tension adjusting member is moved in this manner in'order that thefinger 96 on the tension adjusting member shall move with certainty inadvance of the lug 91 on the drum as these two move when the takeq p isdrawing thread from the supply, and not impede movement or" the drum dueto the" pull of the thread as it passes] around the tension wheel, whichif it occurred, might cause breaking of the thread. I 1

In the thread tension mechanisms above described, it will be observedthat friction between any of the parts is not depended upon to createtension in the thread, with the result that a definite and known tensionmay readily be obtained by a suitable adjustment of the clock spring andthis tension, the amount of whichis j indicated to the operator by thescale referred to, will remain constant until further adjustment of thespring is required according to the nature of the work being operatedupon or a change in the thread being used.

' The nature and scope of the invention having been indicated andmechanisms embodying the invention having been specifically described,what is claimed is: I

1. A sewing machine having, in combination, stitch forming devices, athread tension wheel, a rotatable member, a spring yieldingly holdingthe member from rotation and tensioned by rotation of the member, andmeans for clutching and unclutching the tension wheel and member duringeach stitch formingcycle to cause the member to be rotated with thewheel against the force of the spring by a pull on the thread and to-bereturned independently of the wheel."

2. A sewing machine having, in combination, stitch formingdevices, athread tension wheel, 'a spring to restrain the rotation of the wheelarranged to be tensioned-by the rotation of the wheel, and means actingin timed relation to the stitch forming devices'for connecting anddisconnecting the wheel and spring during each stitch forming cycle.

' 3. A chain stitch shoe sewing machine having, in combinatiomahookedneedle, a. looper, a take-up acting while the needle is in the work, athread tension wheel, a spring to restrain the rotation of the wheel,means for connect.- ing the wheel and spring during the take-up actionof thetake-up, and means for locking the wheel from rotation during theloop drawin stroke of the needle.

4. A chain stitch shoe sewing machine having, in combination, a hookedneedle, a ,looper, a take-up acting while the needle is in the work, aspring pressed auxiliary take-up, a thread tension wheel, a spring torestrain the rotation of the wheel, means forconnecting the wheel andspring during the take-up action of the take-up, means for locking thewheel from rotation during the loop drawing stroke of the needle, andmeans for preventing yielding movement of the auxiliary take-up duringthe takeup action of the take-up.

5. A sewing machine having, in combination, stitch forming devices, athread tension wheel, a rotatable member, a spring yieldingly holdingthe member from rotation, means for clutching and unclutching thetension wheel and member during each stitch forming cycle to cause themember to be rotated with the wheel against the force of the spring by apull on the thread, and means in addition to the spring for returningthe member. P I

6. A sewing machine having, in combination, stitch forming devices, athread tensionwheel, a rotatable drum, a spring yieldingly holding thedrum from rotation, means for clutching and uncl'utching'thetensionwheel and drum during each stitch forming 'cycle to cause-the drum to berotated with the wheel against the force of the spring'by a pull onthe'thread, a rotating member, and means for'clutching said member anddrum to return the drum.

7. A sewing machine having, in combination, stitch forming devices, athread tensionwheel,

a rotatable drum, a coil spring yieldingly holding the drum fromrotation and having one end connected to the drum, a rotatable disk towhich the other end of the spring secured, means for clutching andunclutching the tension wheel and drumduring each stitch iormdiskmanually rotatable to adjust thetension of the spring, and an indicatingdevice actuated by said shaft for indicating the amount of tensionplaced on the thread by the tension wheel when clutched to the drum. 1

8. A chain stitch shoe sewing machine having,

in combination, a hook needle, 9. looper, a takeup acting while theneedle is in the work, a thread tension wheel, a spring to restrain therotation of the wheel, -means for connecting the wheel and spring duringthe take-up action of the take-up, means for locking the wheelfrom'rotation duringthe loop drawing stroke of the needle, and meansoperative upon stopping the machine for unlocking the wheel.

9. A- sewing machine having, in combination, stitch forming devices; athread tension wheel, a spring to restrain the rotation ot'the wheel,means acting in timed relation to the stitch forming devices forconnecting and disconnecting the wheel and spring during each stitchforming cycle, and means for maintaining the spring tensionsubstantially constant during the rotation of the wheel while. connectedto the spring. I

'10.. Achain stitchshoe sewing machine having, in combination, a hookneedle, a looper, a take-up acting while the needle is in the work, athread tension wheel, a spring to restrain the rotation of the wheel,means for connecting the wheel and spring during the take-up action ofthe take-up, and a connection between the take-up and spring formaintaining the spring substantially constant during the take-up actionof the take-up.

11. A chain stitch shoe sewing machine having, in combination, a hookneedle, a looper, a take-up acting while the needle is in the work, athread tension wheel, a rotatable drum, a coil spring yieldingly holdingthe drum from rotation having one end connected to the drum, a rotatabledisk to which the other end of the spring is connected, and means forclutching the wheel and drum during the take-up action of the take-up,and a connection between the take-up and disk for rotating the disk tomaintain the tension of the spring substantially constant during thetake-up action of the take-up.

12. A chain stitch shoe sewing machine having, in combination, a hookneedle, a looper, a take-up acting while the needle is in the work, athread tension wheel, a rotatable drum, a coil spring yieldingly holdingthe drum from rotation having one end connected to the drum, a rotatabledisk to which the other end of the spring is connected, means forclutching the wheel and drum during the take-up action of the take-up,and means for rotating the disk to maintain the tension of the springsubstantially constant during the take-up action of the take-up.

13. A sewing machine having, in combination, stitch forming devices, athread tension wheel, a spring to restrain the rotation of the wheelarranged to be tensioned by the rotation of the wheel, means acting intimed relation to the stitch forming devices for connecting anddisconnectingthe wheel and spring during each stitch forming cycle, andmeans for adjusting the tension of the spring.

14. A sewing machine having, in combination, stitch forming devices, athread tension wheel, a spring to restrain the rotation of the wheel,means acting in timed relation to the stitch forming devices forconnecting and disconnecting the wheel and spring during each stitchforming cycle, means for maintaining the spring tension substantiallyconstant during the rotationof the wheel while connected to the spring,and means for adjusting the initial tension of the spring.

15. A chain stitch shoe sewing machine having, in combination, a hookedneedle, a looper, a take-up acting while the needle .is in the Work, athread tension wheel, a rotatable drum, a coil spring yieldingly holdingthe drum from rotation having one end connected to the drum, a rotatabledisk to which the other end of the spring is connected, means forclutching the wheel and drum during the take-up action of the take-up,means for rotating the disk to maintain the tension of the springsubstantially constant during the take-up action of the take-up, andmeans for disconnecting the disk from its rotating means and foractuating the disk to adjust the initial tension of the spring.

16. A sewing machine having, in combination, stitch formingdevices, athread tension wheel, a spring to restrain the rotation of the wheel,means acting in timed relation to the stitch forming devices forconnecting and disconnecting the wheel and spring during each stitchforming cycle, means for maintaining the spring tension substantiallyconstant during the rotation of the wheel while connected to the spring,means for adjusting the tension of the spring, and an indicating deviceactuated by said adjusting means for indicating the tension of thespring.

FRED RICKS. HAROLD ERNEST ELLIOTT. FRANK COLEMAN CHOICE.

